1. Field of the Invention
The present invention relates to a positive load alignment mechanism, and more particularly to a platform device which is disposed with driving devices which drive the movable platform to perform back and forth, left and right or rotating movement and movable bearing platforms which firmly support the movable platform. Thereby, the alignment mechanism can achieve the objectives of high pressure resistance, simplified structure, high security, high accuracy and all-direction displacement.
2. Description of the Prior Art
A conventional micron/nanometer positioning platform with six-degree of freedom disclosed in TW Pat. No. 093125237 comprises:
A base which includes two linear guideways on both sides; an X-axis saddle which can slide on the linear guideways of the base and each side of the X-axis saddle is disposed with a linear guideway; a Y-axis saddle which can slide on the linear guideways of the X-axis saddle; a first driving device which is installed vertically with respect to the linear guideways and located on one side of the abovementioned base; an X-axis spring return device which is installed between the abovementioned base and the X-axis saddle and located on the other side of the base; a first cuneiform slider mechanism which is installed between the first driving device and the X-axis saddle, and the first driving device, the first cuneiform slider mechanism and the X-axis spring return device work together to drive the X-axis saddle to move along the X axis; a second driving device which is vertically installed to the linear guideway of the X-axis saddle and located on one side of the X-axis saddle; a Z-axis spring return device which is installed between the X-axis saddle and the Y-axis saddle and located on the other side of the X-axis saddle; a second cuneiform slider mechanism which is installed between the second driving device and the Y-axis saddle, the second driving device, the second cuneiform slider mechanism and the Y-axis spring return device work together to drive the Y-axis saddle to move along the Z axis; a third driving device which is installed on the Y-axis saddle to drive a parallel-connected saddle to rotate around Y-axis, and a parallel-connected mechanism which is disposed on the parallel-connected saddle to control the tilt variation on the X-Y axis plane and a Y-axis displacement of a carrying platform.
Though the conventional micron/nanometer positioning platform with six-degree of freedom can realize six-freedom displacement, it still has the following disadvantages:
1. Complicated structure: the X-axis saddle, Y-axis saddle, X-axis spring return device, a first cuneiform slider mechanism, a first driving device, a second driving device, a Z-axis spring return device, a second cuneiform slider mechanism, a third driving device a parallel-connected saddle and a parallel-connected mechanism are positioned one upon the other on the base to form the positioning platform with six-degree of freedom, thus forming a complicated combination and configuration.
2. Poor security: as known from the abovementioned integral structure, with the complicated combination and configuration, the control of the tilt variation on the X-Z axis plane and a Y-axis displacement of a carrying platform will cause excessively strong moving force and rotating force or the separation which cause the impact on the user. So the poor security needs to be improved.
3. Time-consuming: as known from the abovementioned integral structure, a plurality of components is positioned one upon the other on the base to form the complicated positioning platform, so it must consume much assembly time during the manufacturing process.
4. Poor stability: as known from the abovementioned integral structure, a plurality of components is positioned one upon the other on the base to form the complicated positioning platform, so that the displacement of such a structure has poor accuracy and stability.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.